Infertility, impaired fecundity, and live birth/pregnancy ratio in women with epilepsy in the USA: Findings of the Epilepsy Birth Control Registry.

OBJECTIVE

To determine the current risks of infertility and impaired fecundity as well as the live birth/pregnancy ratio among women with epilepsy (WWE) in the USA and whether antiepileptic drug (AED) use is a factor.

METHODS

These retrospective survey data come from the 2010-2014 Epilepsy Birth Control Registry (EBCR) Web-based survey of 1000 WWE in the USA, aged 18-47 years, who provided demographic, epilepsy, AED, reproductive, and contraceptive data. We report risks of infertility and impaired fecundity, live birth/pregnancy ratio, and whether outcomes differ by AED use or category versus No AED.

RESULTS

A total of 978 of the 1000 USA WWE reported reproductive data; 373 WWE had 724 pregnancies and 445 births. An additional 38 WWE (9.2%, 95% confidence interval [CI] = 6.7-12.4%) tried to conceive but were infertile. A total of 72.5% had a live birth outcome for their first pregnancy, 89.0% had at least one live birth for their first two pregnancies, and 61.6% had two live births for their first two pregnancies. Eighty-four of 406 WWE (20.7%, 95% CI = 17.0-2.9%) had impaired fecundity. The risk of impaired fecundity trended higher on AED polytherapy than on No AED (risk ratio [RR] = 1.79, 95% CI = 0.94-3.11, P = .08). The ratio of live birth/unaborted pregnancy (445/594, 74.9%) was similar among WWE on No AED (71.3%), AED monotherapy (71.8%), and polytherapy (69.7%). None of the AED categories differed significantly from No AED. Note that glucuronidated AED (lamotrigine), which had the highest ratio of live birth/pregnancy (89.1%), compared favorably to enzyme-inhibiting AED (valproate), which had the lowest (63.3%; RR = 1.41, 95% CI = 1.05-1.88, P = .02).

SIGNIFICANCE

The EBCR finds 9.2% infertility risk and 20.7% impaired fecundity risk among WWE in the USA. Impaired fecundity trended higher on AED polytherapy than on No AED. Live birth/pregnancy ratio was higher with the use of lamotrigine than valproate. These findings may provide WWE a more objective basis for pregnancy planning.